The present invention relates to a semiconductor package, and more particularly to a semiconductor chip with improved mounting reliability and a semiconductor package having the same.
A flip chip package using bumps has been suggested to shorten electrical signal transfer paths between a semiconductor chip and a printed circuit board.
The flip chip package has a structure in which a semiconductor chip is physically attached to and at the same time is electrically connected with a printed circuit board by bumps formed on bonding pads of the semiconductor chip. The flip chip package provides advantages in that, since electrical connections between the semiconductor chip and the printed circuit board are formed only by the bumps, signal transfer paths are short and excellent electrical characteristics can be obtained.
However, the flip chip package encounters problems in that moisture is likely to leak to the connections and a stress is continuously applied to the connections due to a difference in CTE (coefficient of thermal expansion) between the semiconductor chip and the printed circuit board. Accordingly, fatigue fracture may frequently occur in these connections.
Currently, in order to solve these problems, an underfill process for filling the space between a semiconductor chip and a printed circuit board with a gap-fill substance is performed. However, the underfill process causes other problems in that it is difficult to control processing and voids are likely to be produced in the gap-fill substance.
Moreover, in the case where the underfill process is adopted, wetting may not be properly implemented in a subsequent process. This may deteriorate processing stability and workability, thereby degrading the reliability and productivity of a flip chip package.
In place of adopting the underfill process of filling the space with the gap-fill substance, a method has been proposed in which a semiconductor chip is attached after forming a film or a non-conductive adhesive (NCA) on a printed circuit board. In this method, the production of voids is lessened when compared to the underfill process.
Nevertheless, in the event that the thickness of the film or the non-conductive adhesive is substantial, bumps of a semiconductor chip and a printed circuit board are likely to be improperly connected due to the substantial thickness of the film or the non-conductive adhesive, and a problem may result when transmitting electrical signals.